Online Education For Gem Enthusiasts

  • 6,151 Members
  • 2,136 Articles
  • 109 Gemology Businesses
  • 129,191 Facebook fans

Become a Member

"IGS is a Godsend for me!"

- Charlie Bernheiser, IGS Member

"Thank you for the fantastic adventure!"

- John Parrot, IGS Member

Join Our Thriving Community


2,136 Articles
6,151 Members
109 Directory Listings
129,191 Followers

The world's best gem articles, published weekly.

Most Recent Articles

A Consumer’s Guide to Gem Grading

Learn how gemologists evaluate color, clarity, cut, and carat for gem grading. Consumers can use this information to find the right stone for their needs.

A Guide to Understanding the Inner Workings of the Gem Trade

Based on interviews with gem trade experts, this series of FAQs addresses many topics, such as gem value, investing, insurance, and collecting.

What are Allochromatic and Idiochromatic Gems?

Learn the difference between allochromatic and idiochromatic gems and why some gem species can occur in many color varieties and others occur only in one.

Sphalerite Buying Guide

Our sphalerite buying guide can help you learn how these gems are graded, what to avoid, and how to identify a high quality stone or a bargain in the rough.

Sphalerite Value, Price, and Jewelry Information

Sphalerite occurs in many colors. With a dispersion over three times that of diamond and an adamantine luster, faceted specimens make beautiful additions to gem collections. However, they’re too soft for most jewelry uses.

How to Choose a Diamond

First-time gem buyers may find diamond grades confusing. Our consumer guide explains how diamonds are evaluated and gives advice on how to choose a diamond.

Become a Gemology Pro

  • Certification Course
  • A listing in our business directory
  • Access to our up-to-date gemstone value guide
  • Access to premium articles on tools and techniques
Sign up for a Pro Membership
"Becoming a Pro Member of IGS just made good sense for my business. The gemology resources are fantastic, and my profile lets potential customers know I am serious about colored gemstones. And frankly, if I get any exposure to potential customers it's a no-brainer."
Paul Bierker, Paul Michael Designs
Jeweler, IGS Pro Member

The world's best online resource for gemstone appraisal

Over 15 years, we have assembled detailed pricing and value information for appraising over 70 different gemstones. The values in our guide come from a variety of sources including primary and secondary gemstone dealers, jewelers, miners, and wholesale suppliers of commonly traded gemstones.

View the Price Guide

Take Your Passion for Gemstones to a Whole New Level

For as low as $3/month

See Plans & Pricing